Apparatus for recovering sulfur and ammonia from gas.



E. F. LLOYD.

APPARATUS FOR RECOVERING SULFUR AND AMMONIA FROM GAS.

- APPLIGATIQN FILED APR.21 1913.

1,132,594,: PatentedMar.23,1915.

I i l ERNEST r. LLOYD, or'nnraorr, MICHIGAN.

ArrARA'rUs r03 nncovnnme SULFUR ND AMMONIA rnoivr GAS.

Specification of Letters Patent. Patented llIal. 23, 1915.

Application filed April 21, 1913. Serial No. 762,534.

To all whom it may concern:

Beit known that I, ERNns'rF. LnoYD, a citizen of the United States ofAmerlca, re-

siding at Detroit, in the county of Wayne.

and State of Michigan, have invented certain new and useful ImprovementslI1 Apparatus for Recovering Sulfur and Am-.

monia-from Gas, of which the following is a specification, referencebeing had therein to the accompanying drawings.

This invention relates to an apparatus for washing and cooling gas, andat the same time eliminating and recovering the sulfu and ammoniatherefrom.

5 :The invention consists in the matters here- As herein indicated, awash cooler 1" of any preferred type, or similar' means for taking downthe-tars and reducingthe gas to a proper temperature for scrubbing, hasa gas inlet pipe 9 and a gas outlet pipe 3 whereby the washed and cooledgas is led into a scrubber 4:. a The wash-cooler is of any type whereinthe gas comes into contact with a washing and cooling liquor. scrubberis .of any suitable construction; it

may be arotary scrubber or other such similar apparatus for. removingammonia from gas by washing with fresh water.

The gas is introduced from the outlet pipe 3 of the cooler to theportion or chamber 6 of the scrubber wherein the liquor has at vtained atemperature which is substantially that of the gas, and is also, forpurposes of this particularp'rocess, preferably thelsame .40 as that ofthe liquor in the outlet chamber 6 of the wash cooler. The scrubber hasa fresh water supply pipe indicated at 17 and an overflow pipe 8 fromwhich the excess liquor flows to the crude liquor or works tank orcistern. A pipe 9 leads fromlthe wash cooler to the compartment 6 of thescrubber &. Another pipe 11 from this o'oinpartment is connected to apump 10 whereby the liquor is forced into a heat recoverer 12. A,discharge pipe 14 from the heart-recoverer opens into the upper portionor chamber of a still 1.5. At the point of maximum eflieiency, which inthis type of apparatus apparently is near the lower portion of thesecond section or chamber of the still, the liquor introduced throughthe pipe 14: is

The

tapped off through a pipe 16. This pipe discharges into the coils13 ofthe heat recovery device, and from thence passes through a temperatureregulator 17 and a return pipe 18 to a chamber of the scrubber 4adjacent the chamber 6. The regulator is merely introduced to insure thereduction of the liquor to atemperature closely ap proXimating that ofthe scrubber. Steam is forced into the still, as'from a pipe '20, so asto rise through the sections thereof, and meet the incoming stream ofliquor with its ammonia contents. cal operation, the steam may besupplied fromthe exhaust of pumps 21 that form a part of the washcooler 1. An outlet pipe 32 from the top of the still conducts the vaportherefrom. In the wash cooler refrigcrating coils 23 are used andthese may be connected through the regulator 17 and pipe 24 with coolingcoils 28 'in the base of the ammonia still. the still or condensingcompartment therein is returned through a pipe 26 into the wash cooler 1at a point where the liquor in the latter is at the highest temperature.A thermosta ic valve 27 may b e'us ed for regulating the flow throughthe pipe 24 if desired.

In operation, the liquor from the wash cooler and the water from theintensive scrubber which is impregnated with sulfur and ammonia incombination, is forced into the top of the still where it meets theascending current of steam.- Apparently in the presence of the steam andabove a certain temperature, the descending liquor ;is free(l of thebulk of the sulfur content While still retaining a considerableproportion of the ammonia. The sulfur is ei ther volatilized in a freestate or else forms a gaseous combination with other elements in thestill so that it is free to be discharged therefrom.

This is the point at which. the pipe to the heat recovery-apparatusljisrtapped. into the still. the steam through the stillputlet pipe while theretained ammonia pa ses out into the heat recoverer in the washingliquor, and is returned for further use in the apparatus. The washingliquor from the still is returned to the wash cooler. There issufficient fresh water added continually to the scrubber to preventsurcharging of the liquor with ammonia. Th overflow or excess liquorfrom the scrubber discharges into the work tank or cistern. As a resultthe ordi As a matter of economi-.

Consequently, the sulfur escapes with The liquor frcm the base of naryapparatus for gas manufacture is rendered available for removing boththe sulfur and the ammonia, and allowing substantially complete recoveryof both.

Obviously, changes in details of the construction of the apparatus tomeet the re quirements of particular plants and conditions of servicemay be made without departing from the spirit of the invention, and I donot care to limit myselfito any par ticular form or arrangement ofparts.

VVhat I clain1 is:

1. Apparatus for recovering sulfur from coal gas during the manufacturethereof, comprising a wash cooler, a gas scrubber in series therewith,means introducing liquor from the wash cooler to the scrubber, a stillsupplied with a current of steam, means for forcing combined liquors ofthe cooler and scrubber from the latter into the still into contact withany steam passing therethrough, and means for tappin oh liquor in thestill at a point where it is substantially free from sulfur andreturningit to the scrubber.

2. Apparatus for recovering sulfur fromcoal gas during the manufacturethereof, comprising a wash cooler, a gas scrubber in series therewith,means introducing liquor from the wash cooler to the scrubber, a stillsupplied with a current of steam, means for forcing the combined liquorsof the cooler and scrubber from the latter into the still into contactwith any steam passing therethrough, means for tapping off liquor in thestill at a-point where it issubstantially free from sulfur and returningit to the scrubber, means for circulating a cooling medium through thewash cooler, andmeans for utilizing the cooling medium expelled from thewash cooler for reducing the temperature of the liquors discharged fromthe still and reducing the temperature of the sulfur free liquor tappedfrom the still andreturned to the scrubber.

3. Apparatus for removing sulfur and ammonia from coal during theprocess of rmmufacture thereof comprising a wash cooler, a gas scrubberin series therewith, a still supplied with a current of steam, means forforcing crude liquor from the 'vcash cooler and scrubber to pass throughthe still, means for tapping liquor from the still at a point where itis free from sulfur and returning it to the gas scrubber, a heatrecovery device for equalizing the temperatures between the ingoing andoutgoing columns of crude liquor passing through the still, means forregulating the ten'iperature of the sulfur free liquor discharged fromthe heat recovery mechanism, and means for passing a cooling medium usedin the wash cooler-and heat regulating means through the still.

4:. Apparatus for removing impurities from gas, compris ng means forwashing and cooling the gas with liquor, means for from gas comprisingmeans for washing and cooling gas with liquor, means for scrubbing thegas with fresh water, means for withdrawing a portion of the liquorproduced by the scrubbing means, and substantially distilling the sulfurtherefrom, means for cooling a portion of the sulfur free liquor tosubstantially the temperature at withdrawal and returning it tothescrubbing means andmcans discharging the remainder to the washing andcooling means.

7. In combination apparatus for ren1oving impurities from gas,comprising a wash cooler, a scrubber, a still for bringing liquor intocontact with steam, a heat recoverer for returning to the still heatwithdrawn therefrom, a temperature regulator for controlling thetemperature of a portion of liquor withdrawn from the still, means forwithdrawing liquor fromthe scrubber, passing it through the heatrecover'er and dischar in it into the still means for withdrawing aportion of the liquor from the still and discharging it into ade1ermined point in the scrubber after passing it through the heatrecovercr and temperature regulator, means for discharging the remainderof the liquor from the still into the wash cooler after partiallycooling the same, means for supplying the still with steam and means fordischarging evolved vapors from the still.

in testimony whereof I atlix my signature in presence of two witnesses.

Ell-NEST l LLOYD.

-i litnesses ANNA M. Donn, G. R. STIOKNEY.

